Syrian rebels today claimed responsibility for the deaths of the nation's defense minister, Daoud Rajha, as well as Assef Shawkat, President Bashar al-Assad's brother-in-law, and other top officials.

Demonstrators raise their arms as Syrian opposition flags are seen during a protest against Syria's President Bashar al-Assad in Damascus July 16, 2012. (Reuters)

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GLOBALPOST SYRIA LIVE BLOG

UPDATE: 7/18/12 5:45 PM ET

"The beginning of the end"

Wednesday's assassination of Syrian President Bashar al-Assad’s brother-in-law, along with two senior generals, has been heralded as having transformed power relations in one of the world’s most repressive nations, literally in a flash, write GlobalPost correspondents in Beirut, Hugh Macleod and Annasofie Flamand.

“This is the beginning of the end,” Abdel Nour, a Damascus-based Syria expert, told GlobalPost. “This bomb has blown the mask off and shown that no one is safe. Loyalists cannot believe it, they think that Bashar is god and is protecting all his people. Now other ministers and intelligence people will be terrified that no one can guarantee their safety. They will start preparing their escapes.”

Want to know what the escalating violence in Syria and killing of top officials really means? GlobalPost's senior editor David Case speaks with Daniel Serwer, an expert in Syria and conflicts, to the put the events in context.

GlobalPost: How would you characterize today's bombing? Does this mark a turning point in the civil war? Is this the beginning of the end for the Assad government? Or is this merely a temporary setback?

Daniel Serwer: A lot of people will tell you this is the beginning of the end for the Assad government, but they’ve been saying that for six months and in some cases for a year.

I think it’s really too early to tell. It’s certainly a big strike against the Assad regime. But it’s very difficult to predict at this moment whether it really is a turning point in that victory for the rebellion is imminent – or whether it’s a turning point in that even more chaos is around the corner.

It could also be the beginning of a transition to democracy, or a temporary setback for Assad, though it’s very difficult for me to picture how he’s going to re-impose order even on Damascus, never mind beyond. But that doesn’t mean Assad is coming down; It just means it’s going to be a chaotic situation.

Egyptian police reportedly fired tear gas at protesters outside the Syrian embassy in Cairo on Wednesday, according to Lebanon's The Daily Star. The police took action when demonstrators tried to take down the Syrian flag, said protesters.

"We wanted to take down (President Bashar al-) Assad's flag and raise the independence flag. They started shooting tear gas," said a protester.

The Daily Star noted that Syria recalled its ambassador to Egypt in retaliation for Egypt recalling its envoy following Assad's crackdown on the uprising.

Meanwhile, a Turkish Foreign Ministry official said two more brigadier generals had fled to Turkey overnight, bringing the total number of Syrian generals defecting to Turkey to 20, according to Agence France Presse.

Speaking anonymously, the official said, "Some 330 Syrians including two brigadier generals fled to Turkey Tuesday night." The official said nearly 43,300 Syrian refugees now live in camps near Turkey's border with Syria.

The New York Times posted a few videos allegedly showing Free Syrian Army rebel fighters successfully attacking government forces. Here is one posted by an activist blogger that claims that the FSA destroyed four tanks. As with all reports emerging from Syria, it is not independently confirmed:

Sayyed Hasan Nasrallah, head of Lebanon's Islamic militant group and political party Hezbollah, praised the three Syrian officials who were killed in the Damascus bombing earlier today while speaking at a ceremony marking the 2006 July war, according to Lebanese newspaper The Daily Star.

Assef Shawkat, who was killed in an attack in Damascus Wednesday, wasn't just Syria's deputy defense minister. He was also President Bashar al-Assad's brother-in-law, whom Reuters called "one of the pillars of Assad family rule."

Shawkat has been described in reports as a shadowy figure, a member of the Syrian president's inner circle who had previously served as chief of military intelligence.

US President Barack Obama spoke on the telephone with Russian President Vladimir Putin on Wednesday regarding the latest developments in Syria, according to Russian news agency Interfax.

Reuters reported that Putin's press secretary Dmitry Peskov said, "As a whole the existing exchange of opinions shows that the appraisals of the situation in Syria and final goals of regulating [violence] for both sides coincide."

"Together with that, differences in approaches regarding the practical means of reaching a regulation [of violence] still exist," he said.

Israel's top military and intelligence commanders convened on Wednesday to discuss contingencies in anticipation of the collapse of the regime of embattled Syrian President Bashar al-Assad.

For Israel, the end of the Assad era and the mayhem that Israeli analysts predict will ensue signifies a second volatile border, which, like its frontier with Egypt, after decades of quiet may turn troublesome.

Following two weeks in which several high-ranking Syrian generals defected, the bombing that devastated Syria's elite military cadre is widely being interpreted in Israeli circles as a point of no return for the Assad regime, even if it does not result in its immediate demise.

US Secretary of State Hillary Clinton's position on Syria's infamous president has, to put it diplomatically, evolved.

In March 2011, she said of Syrian President Assad: “There’s a different leader in Syria now. Many of the members of Congress of both parties who have gone to Syria in recent months have said they believe he’s a reformer.”

The British-based Syrian Observatory for Human Rights said nearly 100 people were killed in Syria on Wednesday, including 46 civilians, eight rebel fighters and 43 regime troops, according to The Daily Telegraph.

This unconfirmed video purports to show protesters burning a government security building in the Hajar al-Asswed suburb of Damascus:

For anyone joining us now, the Damascus bombings earlier today killed at least three top officials in President Bashar al-Assad's regime. Among the dead are Daoud Rajha, the defense minister, Assef Shawkat, Assad's brother-in-law and the deputy head of armed forces, and Hassan Turkmani, a former defense minister known as the regime's crisis management chief.

The Guardian noted that state-run TV in Syria reported that Mohammad Ibrahim al-Shaar, the interior minister, had been killed, but the pro-government channel Dounia said he was in stable condition.

There were also unconfirmed reports on the death of Hafez Makhlouf, Assad's maternal cousin and the head of the Syrian Intelligence Agency. Al Arabiya reported that he was killed in the explosion, but there was no follow up or confirmation, according to the Guardian.

The Washington Post published a useful guide to the rest of Assad's inner circle, including his brother, Maher al-Assad, Vice President Farouk al-Shara, Abdul Fatah Qudsiya (the head of military intelligence), Ali Mamluk (the head of General Security Directorate) and Rami Makhlouf (a prominent businessman who controls Syria’s mobile phone network).

Take a moment to look at these amazing photos capturing defining moments in the Arab Spring.

UPDATE: 7/18/12 1:35 PM ET

Venezuela fuels Syria

Another ally helping the Assad regime fight its war against the rebels is Hugo Chavez's government in Venezuela. The South American country has been sending fuel to Syria despite international sanctions, helping fuel the tanks and military vehicles that could play a part in any retaliation against today's attacks in Damascus, writes GlobalPost's Americas Editor Alex Leff.

In a speech in January, Chavez said, "It's the same formula they [the West] used against Libya: inject violence, inject terrorism from abroad and later invoke the United Nations to intervene," while speaking about Syria.

The statement read: "We expect the organizers of the act of terror in Damascus to be identified and for them to face their deserved punishment."

"We see the events as another attempt to further destabilize the situation in Syria."

It added, "We are certain that in the face of hardship, the authorities and the people of this country -- all its true patriots -- will display the required political will and desire to find a rapid peaceful settlement of their internal crisis."

Deputy Foreign Minister Mikhail Bodganov also reiterated Russia's stance, saying, "We’d appreciate our western partners explaining to us how they conceive of using the reference to Chapter 7 against those who are carrying out terrorist acts." Chapter 7 allows the council to authorize measures ranging from diplomatic and economic sanctions to military intervention.

The White House said on Wednesday that President Bashar al-Assad was losing control of Syria, according to Reuters.

"There is real momentum against Assad, with increasing defections, and a strengthened and more united opposition that is operating across the country," said White House spokesman Tommy Vietor, after the bombing in Damascus killed four top officials in the Assad regime, including his brother-in-law.

"We are working urgently with our international partners to push for a political transition in Syria. The international community, including the opposition, has met several times to begin this process and it must continue," he added.

The New York Times reported, "In the aftermath of Wednesday’s deadly attack on President Assad’s inner circle, Syrian state television has apparently tried to project calm by broadcasting images of peaceful streets in the capital, Damascus."

The Times also noted, however, that this video allegedly shot behind rebel lines and broadcast on Al Jazeera shows fierce street fighting in southern Damascus.

UPDATE: 7/18/12 12:50 PM ET

Too early to celebrate?

Syrian activists in Egypt reacted to the news of the bombing in Damascus with an emotional mixture of surprise, joy and skepticism, according to GlobalPost's Egypt correspondent, Erin Cunningham.

“And I’m still worried because of the way that the government, and Syrian [state] television is dealing with this news. It’s not the usual way they deal with things, and I feel like there is more going on than we really know.”

Indeed, Syria’s state television channel, SANA, is notorious in its role as mouthpiece for the Assad government — painting demonstrators as terrorists, downplaying challenges to the regime and spreading false information.

International journalists may be barred from accessing much of Syria, but those experiencing the conflict first-hand continue to find ways to bring images of the fighting and hardship to the outside world. Syrians are sharing their struggles via videos posted to YouTube and social media sites.

The video below shows troops and at least one tank heading south down a main highway into the center of Damascus. According to The New York Times, YouTube user AbdoDumani has posted several videos in the past; however, the timestamp of the video could not be confirmed. The location of the video has been confirmed.

"In the long run we think that this operation is the beginning of the end," George Sabra, a spokesman for the rebel Syrian National Council, said in Milan on Wednesday, according to Reuters.

"It is not important to talk about which individuals did the operation but the most important thing is that this was done by revolutionary activists and the Free Syrian Army," he said. Both the Free Syrian Army and an Islamist rebel group called Liwa al-Islam have claimed credit for the attack.

Urging to UN Security Council to act more swiftly, Sabra said, "The last mission three months of Mr. Annan cost us more than 3,000 victims. We cannot pay this price again."

Speaking of the death of Syrian President Bashar al-Assad's brother-in-law, Assef Shawkat, he said:

"Nominating people to fill jobs is possible. But Shawkat is a family member and very close to Bashar, one of the intimate circle that stood together and which has now vanished. I think the worst thing from Bashar is that many parts of [the] Syrian populace have so far remained on the sidelines and most officers remained loyal in their positions. The dynamic may change now, with people saying let's just abandon this sinking ship."

Zisser said the situation in Syria following Assad's fall will be "the definition of chaos, like what we saw in Libya, with various gangs vying for leadership."

Meanwhile, GlobalPost's Tarnopolsky says the consensus in Israel is that the greatest concern is what will happen to the weapons in Syrian hands.

"If chemical weapons or certain missiles fall into Hezbollah hands, that can change the regional balance," she said.

Israel's minister of defense has called for high-level intelligence and military meetings today in Tel Aviv to discuss possible scenarios, including the desirability of bombing any convoys carrying weapons that may be seen heading towards Hezbollah positions.

The bomb that killed Syrian President Bashar al-Assad's brother-in-law and a number of other high profile regime officials exploded either inside the room where they were meeting or the room next door, sources tell GlobalPost.

For some perspective, this would be like the US Joint Chiefs of Staff meeting in the Situation Room and a bomb going off. That is how unprecedented this security breach is.

GlobalPost's Hugh Macleod, who is based in Beirut and has been following the Syria story closely, calls Wednesday's bombing "the biggest security breach in the history of the four decade dictatorship."

"This wasn't a truck bomb, this wasn't on the street," Macleod said. "This was inside the building where the country's highest security chiefs were meeting."

According to Syria's state news agency, SANA, Rajha wasn't just defense minister: he was also deputy commander-in-chief of the army and armed forces, deputy prime minister, and a general.

The 65-year-old Damascene is described as having a long and decorated military career, and served as the army's chief of staff before his appointment to the Defense Ministry in August 2011.

According to the US Treasury, which imposed sanctions on him in March this year, he was apparently appointed for his loyalty to President Bashar al-Assad's regime. He was one of three ministers to keep their posts in last month's cabinet reshuffle, Reuters reported at the time.

The US Treasury Department announced on Wednesday that it is imposing sanctions on the Syrian prime minister and 28 other cabinet ministers and senior officials, the Associated Press reported.

The move by the US freezes any assets that the ministers may have in areas under American jurisdiction and also bars US citizens from doing business with them. The AP noted that previous sanctions targeted security officials, but the latest round of sanctions covers nearly the entire Syrian government.

There are conflicting reports as to whether the Damascus bombing was a suicide attack or a remote-controlled explosion. It also remains unclear who is responsible for the deadly attacks as both the Free Syrian Army and the Islamist rebel group Liwa al-Islam claimed responsibility.

Syrian state TV reported Wednesday that Hasan Turkmani, Assad's security adviser and assistant vice president, also died in the attack, according to CNN. The other officials confirmed dead include Defense Minister Daoud Rajha and Deputy Defense Minister Assef Shawkat.

Here is raw video of the location where the bombing took place, courtesy of the Associated Press:

UPDATE: 7/18/12 10:25 AM ET

Two different rebel groups claimed responsibility Wednesday for the attack that killed Syria's defense minister and top officials, according to Reuters.

Liwa al-Islam, an Islamist rebel group whose name means "The Brigade of Islam", said in a statement on its Facebook page that it had "targeted the cell called the crisis control room in the capital of Damascus."

"We happily inform the people of Syria and especially the people of the capital that the National Security Bureau, which includes what is called the crisis management cell, has been targeted with an explosive device by the Sayyed al-Shuhada brigade of Liwa al-Islam," the statement read.

"Several regime pillars have been killed," it added.

The Free Syrian Army also claimed responsibility for the attack, according to Qassim Saadedine, a spokesman. "This is the volcano we talked about, we have just started," he said.

Syrian rebel commander Riad al-Asaad, claimed responsibility for the attack on behalf of his forces, saying that they planted a bomb inside the room and detonated it. Syrian state-run TV claimed it was a suicide blast.

"God willing, this is the beginning of the end of the regime," al-Asaad told the AP. "Hopefully Bashar will be next."

Here's a roundup of latest reactions on Twitter, none of which have been confirmed by GlobalPost. Send us tips and information @GlobalPost

UPDATE: 7/18/12 9:00 AM ET

Syrian rebels today claimed responsibility for the deaths of the nation's defense minister, Daoud Rajha, as well as Assef Shawkat, President Bashar al-Assad's brother-in-law, and other top officials, in a Damascus blast earlier described by Syrian state television as a "terrorist bombing," reported Reuters.

BBC News, citing state television, said the government has already replaced the deceased Rajha with General Fahad Jassim al-Freij, former chief of staff of the armed forces.